Table 1.

The changes of amplitudes (μV) and latencies (ms) of N270 and P300 (x̅±SD)

Component	Sites	Amplitude		Latency
		Placebo	MPH	Placebo	MPH
N270	F3	0.70±2.11	-0.40±2.93	5.93±13.46	-12.07±22.73*
	F4	0.99±1.88	-0.39±3.51	9.08±18.34	-14.93±23.57*
P300	P3	0.68±3.97	0.94±2.28	12.31±22.34	-8.92±17.65*
	P4	1.36±3.55	0.79±3.64	6.69±16.86	-6.31±15.19

^*Significantly different from placebo condition at the same electrode (P<0.05).